The Germans liked this gun and prodiced their own Pzgr.40
APCR for it. Care should be taken not to confuse this with the original
French shells.

This was an anti-aircraft gun
(CA=contre-aéroplanes). It was however used in a dual role
against both air and ground targets by the Mobile
Anti-Tank Batteries (BACA).

Sources differ.

Armour Penetration Overview

To be useful, armour penetration figures should specify not only the
gun, range and penetration
achieved, but also the ammunition fired, the angle of
impact, the type of armour
attacked and the penetration criterion used.

The customary
angle of impact when quoting penetration performance is 30º
from the vertical (i.e. 60º from the
horizontal). The French and British measure angle from the vertical,
the Germans and NATO measure
angles from the horizontal. It is also traditional to quote penetration
against homogenous
armour. Performance against face hardened
plate, especially for smaller weapons firing uncapped rounds, can
differ greatly. Homogenous
armour plate has the same density and hardness all the way through,
face harden armour has had its outside hardened or carburised.

The Germans generally tested against Homogenous Armour Plate
at 30º from the vertical. Luckily for us, in 1941,
the German Design Office (Wa Pruef) tested the armour piercing
penetration of many French guns using their own criterion. For this
reason, I have quoted the German designation of the French guns in the
table above.

The French had figures for their own guns, but the rarely seem
to standardise on an angle (25º, 30º
or 35º) and usually use 400m which is never used by
the Germans.

A table for rough conversions
from sloped armour to an equivalent thickness of vertical plate is
given in WO
185/118; well-sloped armour being more
effective than would be indicated by a
simple cosine calculation.

Penetration tables also take no account of non-penetrating
damage. The running gear of all vehicles can
be vulnerable to AP or HE fire from nearly all calibres; in fact the
German 37mm gunners speciallised in firing at the tracks of the heavily
armoured French tanks. Extremely
large calibre rounds can cause
catastrophic damage without needing to penetrate the target;
a 155mm shell, for example, might
completely remove the turret of its target.

Germany began
using welded construction in the
1930s and France used cast armour. Riviting was still used in many
British tanks as well as a few
German and French tanks such as the Panzer 38(t), the AMR 33 and the
hull but not turret of the B1 bis. A shot
hitting an
exposed rivet-head could cause the rivet shank to break off and be
projected into the tank, causing
damage.

The following table can be used to convert penetration values
for shell sizes vs different angles of impact from the vertical:

Shell

10°

20°

30°

40°

50°

60°

70°

37mm

0.99

0.90

0.75

0.57

0.41

0.30

0.22

50mm

0.99

0.92

0.79

0.63

0.47

0.35

0.26

75mm

0.99

0.93

0.82

0.66

0.51

0.39

0.29

88mm

0.99

0.93

0.83

0.67

0.52

0.40

0.31

128mm

0.99

0.94

0.84

0.69

0.55

0.43

0.32

Armour Penetration - French Guns

The following table shows a comparison of muzzle velocity (in
m/s), angle of impact from the vertical and armour penetration (in mm)
from different sources.

Gun

Source

Ammo

m/s

Angle

100m

200m

300m

400m

500m

1000m

1500m

Mitrailleuse de
7,5mm MAC mle.31

French

AP 29

805

15°

8mm
@ 50m

Mitrailleuse de
13,2mm Hotchkiss mle 30

German

AP 35

800

0°

22.5mm

18mm

14mm

AP 35

30°

12mm

10mm

8mm

French

AP 35

800

0°

20mm

APT 35

800

25°

20mm

Canon de
25 SA 35

German

AP 34

920

0°

47mm

40mm

30mm

30°

35mm

30mm

20mm

45°

18mm

16mm

15mm

French

APT 34

880

0°

40mm

35°

32mm

Canon de antichar
25 SA mle 34

French

AP 34

920

25°

40mm

0°

54mm

Mitrailleuse de
25 CA mle 1939

French

AP

875

0°

35mm

Canon de d'infanterie
37 mle 16 TR (or TRP)

French

APHE 92 mle 24

388

0°

12mm

Canon de
37 SA 18

French

APHE 92 mle 24

388

0°

12mm

APC 35

600

35°

20mm

Canon de
37 SA 18 mle 37

German

APC 35

600

30°

25mm

19mm

French

35°

20mm

Canon de
37 SA 38

German

APC 38

705

30°

29mm

23mm

16mm

12mm

French

705

25°

32mm

Canon de
47 SA 34

French

AP 92

450

25°

14mm

480

30°

25mm

Canon de
47 SA 35

German

APC 35

660

30°

39mm

33mm

26mm

20mm

French

30°

40mm

Canon de antichar
47 SA mle 37

German

APCBC 36

855

30°

57mm

50mm

42mm

36mm

French

855

0°

106mm

101mm

97mm

93mm

89mm

72mm

57mm

Canon de
75 SA 35

French

APHE 10M

470

30°

40mm

Canon de
75 mle 1897

German

Unknown

?

30°

62mm

Canon de
75 mle 1897
modifié 1933

French

APHE 10M

580

30°

50mm

French

APHE 16[1]
APHE 18

575

30°

40mm

Notes:

The Obus perforant AL (Allongé
Lefèvre) Mle 1916 (APHE) shell was heavier
than the earlier Obus de rupture Mle 1910M. It contained 350g of HE
instead of
90g. However this did not seem to improve its performance as might be
expected.
The mle 18 had 325g of HE.

Comparision between French/German/British Guns

The following table shows a comparison of muzzle velocity (in m/s) and
armour
penetration (in mm) against homogenous armour plate at a 30°
angle of impact from the vertical for the guns used in
the France 40 campaign.

Country

Gun

Ammo

m/s

100m

500m

1000m

1500m

2000m

MG 34

SmK

785

8

3

SmKH [1]

785

13

8

7,5mm MAC mle.31

AP mle 29

805

6

12.7mm Vickers

AP

785

15

9

13,2mm Hotchkiss

AP mle 35

800

12

8

15mm BESA

AP

884

20

15

Panzerbüchse 39

SmKH

1265

34

14

Boys Mk.I

Kynoch AP

990

21

11

2 cm KwK 30 & 38

Pzgr

780

20

14

9

25 SA 35

AP mle 34
charge forte

950

35

30

20

25 SA 34 or SA-L 37

AP mle 34
charge normal

920

35

30

20

25 CA 39

AP

875

30

25

15

3,7cm KwK 36
3,7cm PaK 35/36

Pzgr

745

35

29

22

20

Pzgr.40 [2]

1020

64

31

3,7 cm KwK 34 (t)

Pzgr.(t)

675

35

30

23

21

3,7 cm KwK 38
(t)

Pzgr.(t)

741

36

31

25

22

37 mle 16 TR
37 SA 18
37 SA 17

APHE mle 92 m 24

388

12

8

37 mle 16 TR
37 SA 18
37 SA 18 mle 37

APC mle 35

600

25

19

37 SA 38

APC mle 38

705

29

23

16

12

2pdr OQF Mk.IX

AP

808

66

50

35

25

4.7cm Pak(t)

Pzgr.36(t)

775

54

48

41

35

47 SA 35

APC mle 35

660

39

33

26

20

47 SA 37

APCBC mle 36

855

57

50

42

36

7,5 cm KwK 40

K Gr rot Pz

385

41

38

35

32

30

Gr38 H1/A [3]

450

70

70

70

70

7,5 cm leIG 18

IGr 38 H1 [3]

305

45

45

45

45

75 mle 1897

APHE mle 10M

580

51

47

43

39

36

75 SA 35

APHE mle 10M

470

41

38

35

32

30

25pdr OQF Mk.I

AP-T

610

82

60

41

28

8,8cm FlaK 18 & 37

Pzgr.39

773

120

110

100

91

84

10,5cm leFH 18

Pzgr

470

63

59

54

50

46

Gr39 H1/A [3]

470

80

80

80

80

15cm sIG 33

Gr39 H1/A [3]

280

160

160

160

160

15cm sFH 13

Gr39 H1/A [3]

460

160

160

160

160

15cm sFH 18

Gr39 H1/A [3]

465

160

160

160

160

Notes:

The SmKH was a very rare (less than 2%) bullet with a
hardened
core of tungsten. It was available until 1942 when lack of tungsten
stopped its production. The Panzer I seems to have been give priority
as it was expected to meet enemy tanks; it had 94 SmKH and
2100 SmK rounds (i.e. approx 5%).

The only Pzgr.40 (APCR) shells produced in 1940 were for
the 3,7cm L/45 KwK36 or the 3,7cm PaK 35/36 which were
equipped with a very small number during the battle of France. Reports
by OKW show that 7,440 Pzgr.40 rounds were fired out of a
total of about 70,000 (i.e. approx 10%). The
4,7cm Pak(t) on the Panzerjäger I received
the Pzgr.40 only in July 1940, the 2cm
Pzgr.40 was not introduced until later in the year and the other Pzgr.40,
such as the 3,7cm(t), in May 1941: i.e. in time for
the Russian campaign.

The German GR H1 shells are HEAT. This explains why armour
penetration does not drop off with range. HEAT peretration is not
usually quoted over 1500m. The HEAT shells quoted here are those in use
in 1940, HEAT shells improved during the war.